The invention relates to an apparatus for making a synthetic filament yarn from filaments which are extruded through a spinneret, then quenched with air in a cooling shaft, and then gathered to form a continuous filament yarn.
In the above process, the filaments exit from the spinneret in a liquid condition, and it is common practice to cool the filaments as they exit from the spinneret so as to solidify the thermoplastic material, of which they consist, to then combine, and finally wind same to form a package. If desired, the filaments are treated, while they are combined to a yarn, in a suitable yarn lubricating device for purposes of a textile quality improvement.
For purposes of cooling, the filaments advance directly below the spinneret through a tube or shaft, with currents of cooling air being directed transversely to the bundle of filaments. These currents of cooling air can be produced by applying positive air pressure at the outside of the tube or shaft. However, it is also possible, especially at high filament speeds, to provide a porous tube or shaft with ambient air at atmospheric pressure surrounding the tube or shaft. In this case, the high filament speeds will generate a vacuum within the tube or shaft so that atmospheric air is sucked in and directed as a current of cooling air transversely of the bundle of filaments.
In this manner, it is possible to obtain on the one hand and as an example for filaments with an extremely fine denier, also known as microfibers, which connote spun filament yarns, filaments having a diameter of about 6-12 micrometers after the spin draw process. However, the extremely fine filaments of microfilament yarns are particularly susceptible to disturbances, i.e., among other things, their Uster values may be adversely affected by turbulences which may occur in the blown air chamber.
On the other hand, however, also industrial yarns which are composed of filaments having a substantially coarser denier, are obtained in this manner. For their cooling or solidification necessary for the takeup, substantially longer blown air shafts or yarn passageways are required than for filaments having a finer textile denier.
It is therefore the object of the present invention to provide an apparatus for reducing, on the one hand, the disturbing influences on the spun filaments, as by the air turbulences in the blown air cooling shaft which may possibly be generated by the advancing yarn, and on the other hand, to reduce the length otherwise necessary of the distance covered by industrial yarns between the spinneret and the takeup station by means of an improved air cooling in the yarn shaft or passageway.